1. Field of the Invention
The present invention relates generally to a label printing and applying machine of a portable type (referred to hereinafter as a "hand labeler"), and more particularly to a printing device for use with the hand labeler, which device can print both machine readable bar codes to be read out by an optical reader and human readable characters to be used for price display and read by the consumer.
2. Description of the Prior Art
As is well known in the relevant art, a continuous strip of labels is wound on a cylindrical core in the form of a roll and unwound therefrom for use. The label strip is comprised of a label tape of a self-adhesive type having its back coated with a pressure sensitive adhesive and of a tape of backing paper adhered in a longitudinal direction to the label tape so as to be peeled therefrom. The label tape is formed at a predetermined pitch with cuts to provide independent labels when it is peeled or dispensed.
In the printing device for use with the hand labeler, on the other hand, a plurality of bar code rings are arranged in parallel with one another. It is, therefore necessary that the bar code rings be in contact with each other without any clearance in between, since the bar codes are comprised of dark bars of predetermined width and of corresponding light spaces. This can be easily understood from consideration of a case in which the bar codes printed with the existence of the spare clearances may possibly be read out as different codes when subjected to the scanning operations of an optical reader. Such difficulty has already been eliminated by several proposals including that of the applicant. In one of these proposals, there is provided means for thrusting a plurality of rotatably juxtaposed bar code rings into contact for printing purposes so as to obtain the desired bar codes. This thrusting means is a unitary member which is made integral with selecting means for turning the bar code rings to select the desired bar codes.
Therefore, although the purpose for printing the desired bar codes can be attained, the operator is liable to make mistakes because both the operation for thrusting and releasing the bar code rings and the operation for turning them to select the desired bar codes are accomplished by the single unitary member. The utilization of a single operating member for two functions can sometimes lead to the performance of the undesired function.
Moreover, most of the commodities which are sold in a supermarket on a large scale are printed with the bar codes on the surfaces of their boxes or bags so as to effect source marking to inidicate the name of a manufacturer. These bar codes are under the auspices of the Association of U.S. Supermarkets and are called "UPC" symbol marks. The bar codes used in the source marking display are made to display only the registered number of the manufacturer and the code number of the food classification. It is customary that the price is not displayed on the food but is recorded in a computer. When the price is determined or changes, it may be processed into the computer through the POS terminal when the bar codes are read out by the scanning operation of the optical reader. This is called a POS (Point-of-Sale) system, which aims at dispensing with the labels themselves and their respective price display operations. More specifically, the price card on a shelf is used in place of the conventional price display on each label. The price is recorded in a computer to eliminate the need for price display on the label, thereby reducing printing costs.
After wide use in the U.S.A., however, the combined system using the source marking and the shelf card has failed to satisfy consumers. This arises from the fact that the consumer cannot check the price of a product after purchasing it because the bar codes are symbols that can be understood only by the optical reader. Thus, a number of regulations were issued concerning the local assigned codes required for price display. As a result, the human readable price display is required as an in-store marking system for each product, together with the source marking bar codes.
It is also the present practice in Japan that both the bar codes and the human readable characters are required by the consumers to be displayed on a label for practicing the POS system as in the U.S.A. In view of this practice, there has been proposed recently an in-store marking hand labeler, in which the bar codes and the human readable characters are juxtaposed widthwise on the body thereof so as to be printed on a label. The label thus used is of such width as to leave a wide spare space in the areas above and below the human readable characters. Therefore, the label becomes expensive and is not suitiable for a product of small size. By the use of the wide labels, the width of the printing device is enlarged in the hand labeler so that the hand labeler becomes large, heavy and bulky as a whole and difficult to handle.